For those who have not completed games in the Xenoblade Chronicles series, this page contains spoilers regarding the plot. Discretion is advised.
During the attack on Rhadamanthus in the twenty-first century, Klaus, one of the scientist of the station, who had blocked all comunications with the Conduit, wanted to use it in order to create a new universe, both as a final effort to protect the station from the attackers and as the final hope he had for mankind, who he had lost faith in.
Galea, who did not agree with Klaus' intentions, tried to stop him. Klaus, however, activated the Conduit anyway, opening numerous portals to other dimensions across the planet. Galea, alognside half of Klaus' body, ended up in a new universe, where she was reborn as Meyneth, the soul of the Mechonis.
The Japanese name is likely a reference to Galatea, the statue which was famously carved by Pygmalion, who then fell in love with her, and subsequently brought to life by Aphrodite. The English name is likely a shortening of the Japanese name.